The present invention relates to a separable bridge, particularly useful for military purposes, and having one or more bridge modules which can be coupled together to form the bridge, with each bridge module having at least one roadway element, lower chord and diagonal element, with the height of the framework formed by the roadway elements, the lower chords and the diagonal elements being adjustable.
A separable bridge is known from the German Patent Document DE-AS 12 07 948 and comprises several bridge elements that can be coupled. The bridge elements each contain a bridge floor (or roadway) plate, lower chords and struts. The bridge elements are designed either as center elements with a horizontally extending roadway or as ramp elements with a sloped roadway. The ramp elements cannot be used as center elements so that, when the bridge is transported, a relatively large number of parts must be carried along.
A separable bridge of the same type is known from the German Patent Document DE-OS 38 14 502 and comprises several bridge elements that can be coupled. The bridge elements represent a framework of bridge floor (roadway) plates, lower chords and diagonal struts Since the lower chords and the diagonal struts can be telescoped or can be fastened at specific coupling points, the height of the structural elements can be adjusted.
It is an object of the invention to provide a bridge of this type in such a manner that is lighter and simpler in its construction.
This and other objects are achieved by the present invention which provides a separable bridge comprising a plurality of bridge modules coupled together to form the bridge, each bridge module having at least one roadway element, lower chords and diagonal elements, with the height of a framework of each bridge module formed by the roadway elements, the lower chords and the diagonal elements being adjustable. The lower chords of a bridge module are shorter than the roadway elements of that bridge module, and the diagonal elements are fastened to ends of the lower chords. The roadway elements have a plurality of fastening points for the diagonal elements and the lower chords, these fastening points being located at different distances from an end of the roadway element. The roadway element, the lower chords and the diagonal elements have constant lengths.
The bridge according to the invention retains the advantages of the bridge described in the German Patent Document DE-OS 38 14 502. These advantages include exposure of a small area to wind, as well as to bombardment. Also, a high variability is provided. This means that either one very long or several short bridges can be built simultaneously by one vehicle. No front end support is required up to approximately 45 meters. The bridge has a low weight and a low transport volume. Additionally, the bridge construction allows a good view of the bridge for a tank driver when driving onto the bridge. When one bridge section fails, only the overall length is reduced and the overall system will not fail. The bridge structure is an open structure, so that the view to coupling points and other critical points is unimpaired. Also, assembly behind the front line is not necessary because all elements are exchangeable. There is no tactical limitation (i.e., decision concerning the length of the bridge is made at the destination).
In addition to these advantages, the bridge according to the present invention is lighter and simpler in its construction than the known bridge since telescoping parts are no longer required (which must have a double-walled design). The height and the slope of the bridge modules are freely selectable within a wide range. The linking of the diagonal elements to the ends of the lower chords allows a lighter construction of the lower chords than in the case of a linking in the center. The very short diagonal elements (shorter than half the lower chords) of the present invention again reduces the overall weight. As a result of the shortness of the lower chords with respect to the roadway, a larger height of the bridge (an arch) is obtained which automatically has a larger length.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.